After about 2 hours, any new window that's supposed to show just has a grey/black outline of the window, and everything in the middle is invisible, showing what would normally be behind the window. Larger programs, like web browsers, won't render at all. Smaller ones like a file folder or pop up windows display as an outline with the invisible part in the middle. This problem doesn't happen to already established web browser or other windows already open.

The attachment shown has a folder that has the outline with invisible part in the middle. The background is my desktop background. The 2 web browsers at the bottom that I shut down and tried to open again, they won't show any outline, completely invisible.

Create a Linux Live flash drive with persistent storage, which exactly matches what you have installed on your hard drive: Same distro, same version, same bittedness (32-bit vs. 64-bit), and boot to it. See if the problem happens there as well.

If the problem persists, then there could be a hardware problem; if you have never updated the video driver in your installed copy of Linux, then it could be a driver problem.

If the problem does not occur in Linux Live, then perhaps something got corrupted or stepped on in your installed copy of Linux. Or, if you have updated your video driver since installing Linux on your hard drive, go back to the video driver which came with your installed copy of Linux.